Have a new 2014 Forest River Forester. Inside there is a black box velcroed into one of the cabinets. The buttons are grouped according to front TV, Rear TV and outside TV. You can select DVD, Cable, ANT, Aux, AV1, etc. I can't seem to find any response from any tv set when pushing any of these buttons. The outside TV has a DVD player under the radio. I was assuming that I could use this box to watch DVD inside coach from that DVD player simply by pushing the DVD button on this black box. Is any one familiar with this system?